Version 1.5.4, jamvm has support for sparc64, but also depends on a
version of classpath that cannot be compiled without some kind of java,
which is not available on sparc64.
The patches attached contain:
1. Update jamvm to 1.5.4
2. Update classpath to 0.98
3. Use ecj + antlr + jamvm-initial instead of jdk when building classpath-0.98
4. New package jamvm-initial-1.5.1 patched for sparc64 which is the jvm used
when running ecj above
5. New package classpath-initial-0.93 which is the java library used by
jamvm-initial
jamvm-initial and classpath-initial are not useful once jamvm and classpath are built.
The packages have been successfully built/installed on sparc64/amd64/i386.
Chances are that it also works on powerpc/arm.
Fix: Patch attached with submission follows:

Original patch did not build on 10-CURRENT and left gjdoc/gjdoc.1
behind from classpath.
Build jars with zip instead of fastjar and add gjdoc/gjdoc.1 to
pkg-plist/Makefile.
Updated patch, new status:
Sucessfully built on:
10-CURRENT/amd64
10-CURRENT/i386
9.0-RELEASE/amd64
9.0-RELEASE/i386
8.2-RELEASE/amd64
8.2-RELEASE/i386
7.4-RELEASE/amd64
7.4-RELEASE/i386
and
8.1-RELEASE/sparc64

State Changed
From-To: open->feedback
Attempt to notify maintainer of both java/jamvm and java/classpath
about the proposed changes to those 2 ports. After approval, we
need to do the new ports, perhaps separately.